Adhesive applicator of the spotter type for folding boxes



Dec. 10, 1968 R. c. STENGER 3,415,221

ADHESIVE APPLICATOR OF THE SPOTTER TYPE FOR FOLDING BOXES Filed Nov. 7, 1967 4 Sheets-Sheet l I N VEN TOR. R z'chard C Sfengl" ATTORNEY Dec 10, 1968 R. c. STENGER ADHESIVE APPLICATOR OF THE SPOTTER TYPE FOR FOLDING BOXES 4 Sheets-Sheet 2 Filed Nov. 7, 1967 INVENTOR.

awn

N n m m r 5 av T C A d W W n x R Dec. 10, 1968 R. c. STENGER 3,415,221

ADHESTVE APPLICATOR OF THE SPOTTER TYPE FOR FOLDING BOXES Filed Nov. 7, 1967 4 Sheets-Sheet 3 v LVVENTUR. Richard (I Sfenger Dec. 10, 1968 R. c. STENGER ADHESIVE APPLICATOR OF THE SPOTTER TYPE FOR FOLDING BOXES Filed Nov. 7, 1967 4 Sheets-Sheet 4 INVENTOR. R/t/zara 6. .Sfenger 4.; ATTORNEY United States Patent 3,415,221 ADHESIVE APPLICATOR OF THE SPO'ITER TYPE FOR FOLDING BOXES Richard C. Stenger, San Carlos, Calif., assignor to Kliklok Corporation, New York, N .Y., a corporation of Delaware Filed Nov. 7, 1967, Ser. No. 681,173 3 Claims. (Cl. 118-243) ABSTRACT OF THE DISCLOSURE The present invention provides a spotter type adhesive applicator capable of applying adhesive spots to the top surface of a substantially horizontally disposed panel of paperboard. One or several fingers, which laterally extend from an oscillating shaft and are normally submerged in a pool of adhesive, are periodically raised by oscillation of the shaft to emerge from the pool, swing beyond a position of maximum elevation above the shaft into a position in which they, finger tips down, contact the board. The amount of adhesive deposited may be controlled by varying the dwell time of the fingers and further by a doctor blade arrangement which limits the thickness of the adhesive adhering to the sides of the fingers as they are being raised from the pool.

The present invention relates to improvements of spotter type adhesive applicators particularly well suited for use with adhesives of the hot metal type.

Devices for spotting adhesive on a panel of folding box board are known in which adhesive is periodically transferred from a receptacle containing a pool of adhesive by means of an assembly comprising a plurality of curved fingers and an oscillating shaft on which the fingers are mounted, the tips of the fingers being normally submerged in the pool and being capable of being raised, by oscillation of the shaft about its axis, to a position above the pool level to transfer adhesive to a panel of folding box board against which the finger tips are moved.

In the known device adhesive spots are being applied to the under-surface of flaps extending at a downward slant of about 45 degrees from the main panel of the hinge cover of a folding box which is about to enter a vertical compression shaft. The amount of adhesive which is applied is not variable and is the amount which happens to cling to the finger tips at the end of their travel into a 45 degree position in which the finger tips point upwardly.

According to the present invention devices of the aforementioned type are improved by the provision of a substantially horizontal support on which the panel is supported, and an arrangement in which the finger tip or tips are moved on an arc beyond an intermediate position of maximum elevation above the shaftto a final position in which the finger tips are downwardly directed and contact the upper surface of the folding box board panel on the support.

In this position adhesive adhering to the finger or fingers tends to flow towards the tip or tips and permits the amount of adhesive which is applied to be varied bya variation of the time the finger tips dwell on the panel surface.

The amount of adhesive is further controllable by doctor blades past which the fingers move in close proximity after emerging from the pool. The doctor blade or blades limit the thickness of the adhesive adhering to the fingers.

A further manner of controlling the amount of applied adhesive is by means of the motion mechanism which oscillates the shaft. The more gradual the deceleration of the fingers immediately prior to the contact with the board 3,415,221 Patented Dec. 10, 1968 surface, the smaller the amount of adhesive which is deposited. Rapid deceleration increases the amount.

The fingers may advantageously be made to have flat sides, for example by making them from sheet stock to produce blunt elongated finger tips and fiat finger sides for convenient control of the adhesive by means of doctor blades.

Devices incorporating the present invention are particularly well suited for use in box forming machines of the plunger-and-die type in which the blank is deposited over the mouth of the die by a suitable blank feeder and remains there for a brief period of time during which the feeder withdraws and the plunger approaches.

An adhesive spotter may conveniently be placed adjacent the box forming die in a position in which the finger or fingers reach over and spot adhesive on the blank during its brief period of rest.

These and various other objects, features and advantages of the invention will appear more fully from the detailed description which follows, accompanied by drawings showing for the purpose of illustration a representative embodiment of the invention. The invention also resides in certain new and original features of construction and combination of elements hereinafter set forth and claimed.

Although the characteristic features of this invention which are believed to be novel will be particularly pointed out in the claims appended hereto, the invention itself, its objects and advantages, and the manner in which it may be carried out may be better understood by referring to the following description taken in connection with the accompanying drawings forming a part of it in which:

FIGS. 1 to 4 are perspective views of an adhesive spotter in successive stages of operation.

In the following description and in the claims various details will be identified by specific names for convenience. The names, however, are intended to be generic in their application. Corresponding reference numerals refer to corresponding parts in the several figures of the drawlngs.

The drawings accompanying, and forming part of, this specification disclose a device constructed solely for the purpose of testing and proving the principles and operation of the invention, hence discloses specific details. It should be understood that structural details may be modified in various respects without departure from the principles of the invention and that the invention may be incorporated in other srtuctural forms than shown.

Referring to FIGS. 1 and 2, an appropriately heated receptacle 11 is disposed alongside a substantially horizontal support 12 on which a blank B, or at least a portion of a blank, rests to which adhesive is to be applied.

In the illustrated example the blank comprises a box body portion 13 and a hinge cover portion 14 articulated thereto along a cover hinge line 15.

The blank is subdivided into individual panels by fold lines and flaps are defined by cuts or notches. Thus, a wall panel 16 is articulated to a bottom panel 17 along a bottom fold line 18. A further wall panel 19 is articulated to the bottom panel along a further bottom fold line 20 and has a corner flap 21 articulated thereto along a corner fold line 22, the flap being separated from the panel 15 and is mounted in bearings 26 and 27. A crank 28 at the far end of the shaft permits the shaft 25 to be rocked or oscillated about its axis and a pin 29 extending from a collar 30 clamped to the shaft and cooperating with a fixed stop 31 limits the extent to which the shaft may be rocked in a clockwise direction, viewing the near end of the shaft.

The crank 28 of the illustrated example is designed for manual operation, but it is obvious that in a production machine the crank would be operated, through appropriate linkage from the drive mechanism ofthe box erecting machine, to operate in timed relationship with the blank feeder which deposits the blank on the support 12 or with the plunger, or other blank folding device.

A pair of blades 32 made from sheet material are secured to the shaft at 33. The blades are contoured to provide a pair of fingers 34 having blunt ends or tips 35 of a contact area which determines the area of the adhesive spot to be produced.

The tips are preferably so disposed as to come to rest on the surface of the blank B simultaneously after clockwise oscillation of the shaft 25.

The sides of the fingers 34 are flat and pass through slots 36 of a doctor blade 37, the doctor blade bein adjustably mounted at 38. The purpose of the doctor blade is to wipe all but a film of predetermined thickness from the side of the fingers when the fingers emerge from the pool 24 in which they are normally submerged (FIG. 1).

In the operation of the device the shaft 25 is oscillated about its axis causing the fingers 34 to emerge from the pool with a coating of adhesive thereon. A portion of the adhesive is removed as the fingers pass the doctor blade 37. The finger tips then reach an intermediate position of maximum elevation above the shaft axis and thereafter descend, tips down, until they make contact with the blank B (FIG. 3) depositing thereon a pattern 39 of adhesive spots or dots corresponding to the pattern of the tips 35. The pattern is best seen in FIG. 4 showing the fingers on their return to the pool.

Referring to FIG. 3, it is evident that in the downwardly directed position adhesive clinging to the fingers tends to run towards the tips. The amount of adhesive which is deposited is therefore dependent on the length of time fingers remain in the position of FIG. 3. Another factor determining the amount of adhesive deposit is the abruptness with which the fingers are brought to a stop when contacting the blank. A sudden stop results in a deposit of more adhesive per spot than a gradual stop.

Obviously a second set of fingers could be mounted on the shaft 25 adjacent the bearing 26 to apply adhesive for the near corner of the blank and a corresponding applicator be provided for the far portion of the blank B.

What is claimed is:

1. A device for applying adhesive spots to a panel of folding box board in which device adhesive is periodically transferred from a receptacle containing a pool of adhesive by means of an assembly comprising at least one finger and an oscillating shaft on which the finger is mounted, the tip of the finger being normally submerged in the pool and being raised, by oscillation of the shaft about its axis, to a position above the pool level to transfer adhesive to a panel of folding box board against which the finger tip is moved, characterized in that a substantially horizontal support is provided on which the panel is supported and that the finger tip is moved on an are beyond an intermediate position of maximum elevation above the shaft axis to a final position, finger tip down, in which final position the finger tip contacts the folding box board panel on the support.

2. A device according to claim 1 in which a doctor blade is provided in a position in which the finger passes the blade on its way up from the pool and before reaching the intermediate position of maximum elevation, the doctor blade being sufiiciently close to the finger to limit the thickness of the adhesive adhering to the sides of the finger.

3. A device according to claim 2 in which the finger is formed from sheet stock so as to present fiat lateral surfaces.

References Cited UNITED STATES PATENTS 748,428 12/1903 Simonson 118243 1,194,244 8/1916 Schwartz et al. 118-243 XR WALTER A. SCHEEL, Primary Examiner.

R. I. SMITH, Assistant Examiner. 

